1. Technical Field
The present invention relates to a facsimile machine to which a data terminal device such as a personal computer is connected.
2. Background Art
Facsimile machines are able to send and receive arbitrary image data to and from a remote communication device so that they are widely used in offices and homes. On the other hand, data terminal devices such as personal computers having many functions are also developed. In recent years, a personal computer is connected to a facsimile machine as a data terminal device to provide a facsimile-personal computer system. In this combined system, the facsimile machine and personal computer are operable in a cooperative manner.
In this facsimile-personal computer system, the facsimile machine can function as a scanner for the personal computer if it is used to scan an image and send it to the personal computer. The personal computer then modify or process the image data. The facsimile machine can also function as a printer for the personal computer if it is used to receive image data from the personal computer, which image data is prepared by the personal computer, and print it on a recording sheet. The facsimile machine can further function as a modem for the personal computer if it is used to receive and send image data from and to a remote communication device since the facsimile machine is connected to the remote communication device via a communication line and is able to perform facsimile communication between the remote communication device and itself.
When the above described conventional facsimile machine is used as a scanner for the data terminal device such as a personal computer, communication capability of the personal computer (e.g., how the personal computer receives data from the associated facsimile machine) is generally unknown. Accordingly, the conventional facsimile machine has the following problems.
Before sending image data to the personal computer from the facsimile machine, the facsimile machine scans the image, codes it, stores it in its memory, and conducts handshaking with the personal computer to confirm communication capability of the personal computer. Therefore, if scanning resolution (or scanning line density) of the facsimile machine is finer than the communication capability of the personal computer (e.g., if the facsimile machine scans the image at high resolution but the personal computer does not have such a high resolution), the data form should be adjusted to a lower resolution before data transmission to the personal computer so that it conforms with the communication capability of the personal computer.
Specifically, if the facsimile machine scans the image at a superfine mode (15.4 lines/mm line density) but the personal computer only has a fine mode (3.85 lines/mm line density), then the image which has been scanned, coded and stored by the facsimile machine should be coded again such that the image data to be transmitted matches the resolution of the personal computer. Thus, the processing for image data transmission to the personal computer is complicated and time consuming.